1. Field of the Invention
The invention relates to plate links for a plurality of different plate-link chains for belt-driven, conical pulley transmissions. The invention further relates to a plate-link chain that is composed of such links.
2. Description of the Related Art
FIG. 1 shows, in a top view, a section of a known plate-link chain as it is utilized as an endless torque-transmitting means for belt-driven, conical pulley transmissions. Such belt-driven, conical pulley transmissions have two pairs of conical disks around which the plate-link chain circulates. The distances between the conical disks of the pairs of conical disks are adjusted in opposite directions in order to continuously adjust the transmission ratio of such a belt-driven, conical pulley transmission.
One such plate-link chain is composed of individual plate links 10 that are arranged in several rows I, II, III, and so on, that extend next to one another in the longitudinal direction of the plate-link chain. At least some of the plate links of adjacent rows are offset relative to each another, so that pins 12 that extend transversely through the plate-link chain, establish a longitudinal and transverse connection of the plate-link chain.
FIG. 2 shows a side view of a plate link 10. As can be seen, each of the pins is formed from a pair of rocker members 14 and 16, collectively designated by 12, wherein the side surfaces of the rocker members 14 that face away from one another are in contact with inner surfaces of a plate link opening 18, and the surfaces of each pair of rocker members 14, 16 that face one another form rolling surfaces on which the rocker members 14 and 16 roll against each other during curving of the plate-link chain.
The end surfaces of the rocker members that extend laterally from the plate-link chain form bearing surfaces that come into frictional contact with the conical surfaces of the conical disks of the belt-driven, conical pulley transmission.
One structural object in the design of such plate-link chains is to make the spacing T of the plate-link chain, that is, the distance between two adjacent pins 12 or rocker member pairs 14, 16 as small as possible. The longitudinal width D of the perpendicular web of the ends of plate link 10, required for reasons of strength, is controlling with regard to that distance. A small spacing between adjacent pins 12, in which as many end surfaces as possible of the pins or rocker member pairs are simultaneously in frictional contact with the conical surfaces of the conical disks, produces increased torque transmitting capacity, and equalizes the stress on the individual components.
FIG. 1 shows a plate-link chain in the so-called double plate link connection in which the arrangement of the plate links repeats after each two spacings, or in the lateral direction of the chain preferably every two rows. As can be seen, the spacing is determined by twice the thickness of the rocker members (or the diameter of a pin) and twice the longitudinal width D of the plate link ends plus a slight distance between successive plate links.
A distinctly smaller spacing is achieved with the so-called triple plate link connections in accordance with FIG. 3, in which the pattern repeats each three spacings, or preferably every three rows in the transverse direction of the plate-link chain. As can be seen, the spacing in the case of the triple plate link connection is twice the thickness of the rocker members or the diameter of a pin, plus the longitudinal width D of a plate link end plus a slight distance between the plate link and the pin or rocker member. Thus, the triple plate link connection in accordance with FIG. 3 permits a smaller spacing T than the double plate link connection in accordance with FIG. 1.
Relative to FIG. 2, it can be pointed out that the line 20 there shows the right-hand edge of the region of the adjacent plate link 101 of the arrangement in accordance with FIG. 3, which is visible through the plate link opening 18.
Based upon acoustic excitation and noise comfort, it is advantageous if the plate-link chain has different spacings between adjacent pins 12 or rocker member pairs. In that way individual sound impulses can be reduced or suppressed.
FIG. 4 shows a section of such a plate-link chain with a short spacing TK next to a long spacing TL. That is possible by utilizing two different kinds of plate links, a short plate link 10K and a long plate link 10L, that differ essentially only as a result of the length of the plate link opening 18 (FIG. 2) measured in the longitudinal direction of the plate-link chain.
A problem that arises in the case of the construction of the plate-link chain in accordance with FIG. 4, which is arranged using the same triple plate link connection as the chain in accordance with FIG. 3, resides in that the plate link 10x, which can be a short or a long plate link and which follows the uppermost plate link 10K toward the right in accordance with FIG. 4, no longer overlaps the plate link 10K1 that follows the plate link 10K in the adjacent row toward the right, so that the plate link 10x can be displaced laterally to the longitudinal direction of the plate-link chain along the pin or the rocker member pair.
The object of the invention is to provide a possibility for manufacturing plate-link chains with different spacings with the fewest possible different links, without the occurrence of the problem that was indicated by means of FIG. 4, that plate links have undefined positions in the transverse direction of the plate-link chain.